The present invention is broadly concerned with the production of magnetochemical particles which can be magnetically stimulated to produce visible displays, and in particular color displays.
Magnetochemistry is the utilization of magnetic field forces to trigger spontaneous chemical reactions, and the background of this art is to be found in the prior U.S. Pat. Nos. 3,281,669; 3,512,169; 3,882,507; 3,911,552; and 3,922,687. The last three patents disclose and describe the structure of high sensitivity magnetochemical particles in which two plated, pre-oriented magnetic metal spheres and joined with their directions of orientation in parallel relation, and such that, when placed in a suitable chemical environment and subjected to a magnetic field, opposing forces are generated between the spheres causing them to spring apart and thereby initiate a chemical reaction between the exposed junction of the spheres and a surrounding chemical environment.
The patents further teach that these triggering elements may be incorporated into color forming liquids suspended in droplet form in a resin medium coated upon a support material. Visual patterns in color are produced from the exposure of the coated material to an appropriate magnetic field.
The above-mentioned U.S. Pat. No. 3,882,507 discloses and teaches the broad concept of positioning and aligning plated magnetic metal spheres so that their preferred directions of orientation for magnetic field propagation are parallel, and while so positioned abrading small surface areas of the spheres, then bonding the two spheres together to provide discrete pairs of such tiny magnetic metal spheres as illustrated by FIGS. 2, 3, 4 and 5 of the patent.